var http = require('http');
http.createServer(function (req,res){
    res.setHeader('Content-Type','text/html');
    console.log(res.getHeader('Content-Type'));
    res.removeHeader('Content-Type');
    console.log(res.getHeader('Content-Type'));
    console.log(res.headersSent);
    res.sentDate = false;
    res.statusCode = 400;
    res.write('hello');
    console.log(res.headersSent);
    res.end();
}).listen(8089,function () {
    console.log('server started');
})